Michael Joseph "Mike" Farrell, Jr. (born February 6, 1939) is an American actor, best known for his role as Captain B.J. Hunnicutt on the television series M*A*S*H (1975–83). He is an activist for various political causes.

Farrell's big break came in 1975 when Wayne Rogers unexpectedly departed M*A*S*H at the end of the third season. Farrell was quickly recruited for the newly created role of B.J. Hunnicutt, along with co-series lead Harry Morgan, who replaced McLean Stevenson, also at the end of the third season, opposite Alan Alda. Both Morgan and Farrell were big fans of the M*A*S*H series during its early seasons before they both joined the cast, with Morgan having also appeared as "General Bartford Hamilton Steele" in the season-three episode "The General Flipped at Dawn" (for which he won an Emmy Award for Best Guest Role in a Primetime Comedy Series).[4] Farrell stayed with the series for its remaining eight years on the air. During that time, he wrote five episodes and directed four.

His favorite episode is “The Interview.”

In a recent interview, Farrell discussed the byplay between his M*A*S*H co-stars David Ogden Stiers and Harry Morgan: "David was like a rock; when he was concentrating, when he was being Charles Emerson Winchester III, you just couldn't get him, except for Harry Morgan. Harry could look at David and reduce him to a puddle of tears without turning an eye. David said, 'When he [Harry] looks at me and flares those nostrils; and he would be gone,' it would be such a wonderful thing to see this great big guy just reduced to a giggling idiot by Harry. Unfortunately, all I can do is to tell you, we had great fun doing the show; and much of it was laughing at some silly gag that one of us had pulled on the others."[5] Farrell continued to stay in touch or to have dinner with his on-screen commanding officer, until Morgan's death on December 7, 2011. Farrell said of his death: "He was an imp. As Alan once said, there's not an unadorable bone in the man's body. He was full of fun, and he was smart as a whip."[6] Prior to Morgan's death, he also added of his mentor's six-decade career: "He was one of the foundational pieces of the industry. Such honors routinely go to stars, but also belong to Morgan and other character actors who provide 'the grit and the substance and the context' for so many films and TV shows," to sum it up, he stated: "Harry has been that, par excellence, for many years."[7]

Since M*A*S*H, Farrell has guest starred in Murder, She Wrote; Justice League; Desperate Housewives; and many others. Farrell voiced Jonathan Kent in the Superman (1996) animated series, with wife Shelley Fabares voicing Martha Kent. He also hosted several "National Geographic Presents" specials, and starred in a number of TV movies, including Memorial Day (which he co-produced); Sex and the Single Parent; Prime Suspect; Choices of the Heart; Private Sessions; Vanishing Act; A Deadly Silence; The Price of the Bride; Incident at Dark River; The Whereabouts of Jenny; and Silent Motive. He has done two one-man shows: JFK, a One Man Show for PBS and, on stage, a national tour of David W. Rintels' play Clarence Darrow. In 1983 Farrell starred in the movie Memorial Day.

In 1999 Farrell was given the part of veterinarian Jim Hansen, the father of the lead character Dr. Sydney Hansen, portrayed by Melina Kanakaredes, on the NBC-TV melodrama series Providence.

In his portrayal of Sydney's father, Farrell played opposite Concetta Tomei, who portrayed his wife, Lynda Hansen. Tomei's character died during the first episode of the series, but continued to appear as a ghost/memory in vignettes of later episodes. Farrell appeared in 64 of the 96 episodes.

Even before he was well-known, Farrell was an activist for many political and social causes. He was co-chair of the California Human Rights Watch for ten years, was on the Board of Advisors of the original Cult Awareness Network, and has been president of Death Penalty Focus for more than ten years,[10] being the first person to be awarded its Human Rights Award, subsequently named after him in 2006. He received PETA's Humanitarian Award in 2001, and narrated a public service campaign for them about animal abuse.[11][12]

Farrell wrote an autobiography, Just Call Me Mike: A Journey to Actor and Activist (ISBN 1933354089), published in 2007. The book covers his working-class childhood in West Hollywood, his break into show business, his personal life, and his increasing involvement in politics and the human rights movement in the United States, Cambodia, and Latin America. His second book, "Of Mule and Man," is a journal of his five-week, 9,000-mile drive around the U.S. to promote the paperback edition of his first book.

In August 1963, Farrell married actress Judy Hayden, who was working as a high school English and drama teacher in Laguna Beach, California.[16] They were separated in 1980 and divorced in 1983. They have two children, Michael and Erin. On M*A*S*H, Hunnicutt's daughter also was named Erin. Also on M*A*S*H, in the episode 'The Colonel's Horse', Hunnicutt's father-in-law is Floyd Hayden, Hayden coincidentally being the maiden name of Farrell's wife, Judy. Judy Farrell also worked on M*A*S*H from 1976-1983 as Nurse Able, one of the few nurses with a recurring role.